During the Spanish Colonial Period (1542-1821) in the American Southwest, the Spanish empire was competing for control over resources with the British, French, and Russian monarchies. They attempted to link colonies in the Spanish territories, later known as the New Mexico and California, by establishing trade routes to form a passageway across the entire Southwest desert region. The Old Spanish Trail was used commercially to link the towns that would later become Los Angeles, California, and Santa Fe, New Mexico, from 1829 until 1848. The abundant spring water available in the Las Vegas (meaning "the meadows" in Spanish) Valley made it an ideal resting point on the trail.

The presence of the valley springs also drew the Southern Paiute Indians, a nomadic people moving frequently during the year, who made the valley their winter homeland. They raised small crops near the springs in the valley, which provided water and food for the Indians inhabiting the area and later for travelers making their way across the desert.

The Las Vegas Valley would become an attractive place for other European-American settlers as well. One group of settlers looking for a new home was the Mormons--also known as the Church of Jesus Christ of Latter-day Saints--a religious sect organized by Joseph Smith in New York in 1830. Based on the Book of Mormon, which Smith said was revealed to him by heavenly messengers, this religious body felt called to restore the authentic church established by Jesus and his Apostles. The history of the Mormons is dramatic--filled with persecution, an exodus from the eastern part of the United States, and ultimately successful establishment of a thriving religious society in a desert. The Mormons formed in upstate New York, an area where the Second Great Awakening was most popular as the United States underwent a widespread flowering of religious sentiment and unprecedented expansion of church membership. The group was forced to move several times because of conflicts with residents in various places where they settled, including Ohio, Missouri, and Illinois. They were accused of blasphemy and inciting slave insurrections. After Smith was killed by an angry mob in Illinois in 1844, it became necessary for the Mormons to find a new home once again.

A new leader emerged to guide the Mormons to a new Zion at the Great Salt Lake. Under the direction of Brigham Young, they began an arduous journey West to what would become Utah, where they arrived in July of 1847. In 1848, after the war with Mexico, the United States acquired the majority of what now constitutes the American Southwest. The Mormons petitioned Congress to become the State of Deseret, a word from the Book of Mormon signifying honeybee which was considered an industrious creature, but they were only allowed territorial status. Congress established the Territory of Utah, named for a local Indian tribe, and President Fillmore appointed Brigham Young governor in 1851. Young also became superintendent of Indian affairs. He oversaw the building of Salt Lake City and hundreds of other southwestern communities.

In the middle of the 19th century, the idea of "Manifest Destiny"--a phrase used to explain continental expansion by the U.S.--was embraced by many American people, including the Mormons. They began an industrious campaign to colonize Utah and beyond, establishing hundreds of settlements throughout the West and Southwest. As part of this process, Brigham Young called on volunteers to create a Las Vegas Mission, which would be strategically located alongside the Mormon Road (a portion of the Old Spanish Trail between New Mexico and California), halfway between the Mormon settlements of southern Utah and the San Bernardino Mission in southern California. There were eventually 96 settlements that included Lehi, Provo, Payson, Nephi, Fillmore, Beaver, Parowan and Cedar City. Meanwhile, the discovery of gold in California in 1848 made southern Nevada a corridor for westward emigrants and gold seekers. A gold seeker wrote in his diary on November 21, 1849 about stopping at the Las Vegas creek. Offering the only reliable supply of water for a 55-mile stretch along the Mormon Road, the Las Vegas Valley's springs were important for watering the mules, horses and oxen of travelers crossing the region's harsh desert environment. With the opening of the San Bernardino settlement in 1851, there was an additional need for a way station at the Las Vegas springs to provide supplies and rest. The mission the Mormons established as part of the Church's westward expansion out of Utah became the first non-native settlement in the area, and the Mormons hoped to bring the American Indians into their flock. Although the Mormons occupied the site only from 1855 to 1858, it affected the development of what was to become southern Nevada.